#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

from oslo_db.sqlalchemy import utils


def upgrade(migrate_engine):
    if not utils.index_exists_on_columns(
            migrate_engine, 'messages', ['expires_at']):
        utils.add_index(migrate_engine, 'messages',
                        'messages_expire_at_idx', ['expires_at'])
